Method of covering shoes

ABSTRACT

A method for covering shoes on the feet of a wearer with a protective sanitary shoe wrapper formed of heat-shrinkable material is disclosed, wherein individual shoe wrappers are positioned at a heat-shrink station in an open configuration to receive and enclose a shoe on the foot of a wearer; after the insertion of the shoe, heat is applied to the wrapper to heatshrink it and conform it to the show.

United States Patent 1151 3,694,939

Chen 51 Oct. 3, 1972 [54] METHOD OF COVERING SHOES 3,359,658 12/1967Price ..36/9 R 72 I t z All Ch B 11 vi ,Mi h 3,419,929 1/1969 SHOW etal..12/142R E 2 ti i N 3,525,110 8/1970 Batchelder et al. ..36/72 cssrgnee: n ra nes, ew

York Primary Examiner-Patrick D. Lawson 22 Filed: Oct. 27, 1970Arwrrwkcuflisi Morris & Safford [21] Appl. No.: 84,328 [57] ABSTRACT Amethod for covering shoes on the feet of a wearer [52] $8.8]. ..36/7.3,36/72 C, 12/142R with a protective sanitary shoe wrapper formed of 2; iA43d 9/00 heat-shrinkable material is disclosed, wherein in- 1 e o c l lg g g dividual shoe wrappers are positioned at a heat-shrink I stationin an open configuration to receive and en- 56] R f cud close a shoe onthe foot of a wearer; after the insertion e erences of the shoe, heat isapplied to the wrapper to heat- UNTED STATES PATENTS shrink it andconform it to the show.

2,648,854 8/1953 Otsuka ..36/72 C.

30 Claims, 11 Drawing Figures PATENTEDUBTIB I972 3,694,939

SHEET 1 BF 6 INVENTOR. uqlleiz C/zen/ ZQWM hi/22 I ATTOH METHOD OFCOVERING SHOES This invention relates generally to heat-shrinkableovershoes and to a method of applying heat-shrinkable overshoes to shoeswhile the shoes are being worn.

Disposable overshoes have been proposed in the past for use in variousfacilities in which sterile conditions must be maintained, e.g., forcovering the shoes of physicians or other personnel working in operatingor clean room facilities. Such overshoes are often utilized in hospitaloperating rooms where it is necessary to prevent contamination of theatmosphere and floor from bacteria carried on street shoes, thereby toavoid infection of the patient. Further, it is frequently necessary tomaintain extremely clean conditions in industrial and commercialinstallations during production processes. This is particularlynecessary in the aerospace and electronics industries, where delicateelectronic components must often be protected from chemical and physicalcontaminants, minute particles of dirt, fine metal particles, etc.

The sanitary overshoes which have previously been proposed for use inthese areas have been generally formed from a variety of materials,including paper, natural synthetic fibers, and plastic films. Theseovershoes have also been formed in a variety of manners, as by gluing,sewing, or heat-sealing the various parts to form completed shoecoverings. These coverings are generally provided with elastic tops,tiestrings, snap fasteners, and the like to secure them to the shoe andto facilitate later removal thereof.

While these prior art boots have been helpful in maintaining sanitaryconditions in hospital operating rooms and other clean rooms, they havenumerous disadvantages. Thus, they are generally cumbersome inappearance and are difficult to apply and remove. Moreover, the priorart boots are relatively expensive to produce and do not offer completesanitary protection for hospital use. They are not fully sealed to theshoe, but rather are generally loose-fitting with numerous folds andopenings through which bacteria and contaminants may escape to theatmosphere or floor of the operating room. Due to their expense, many ofthese boots must be reused, thereby requiring time consuming and costlysterilization procedures which, it is noted, are generally not fullysatisfactory. Finally, due to their cumbersome size and bag-likecharacter, the prior art boots are not only uncomfortable and untidy butthey are also difficult to walk in. Thus, for example, such boots mayhinder the mobility of the physician in the operating room.

Also, there is a need for cheap disposable protective foot coverings toprotect the shoes in unexpected inclement weather. Such coverings couldconveniently be dispensed from coin-operated machines in public placessuch as airports, railroad stations, and the like, for example.

Accordingly, it is an object of the present invention to provide amethod and apparatus for protecting the shoes, particularly those ofclean room and operating room personnel, with a shoe wrapper which isdisposable after a single use.

Another object of the invention is to provide a relatively simple andinexpensive method of covering a shoe with a sanitary wrapper.

A still further object of the invention is to provide a method andapparatus for protecting a shoe with a sanitary wrapper by automaticapplication of the wrapper tightly to the shoe to maintain a goodappearance conforming to the shoe, thereby to facilitate walking.

Yet another object of the invention is to provide a method of coveringeither the left or the right'shoe of the wearer with a singleundifferentiated wrapping.

In accordance with an aspect of this invention, a method and apparatusfor protecting a shoe with a sanitary shoe wrapper are disclosed whereina supply of wrappers, formed of heat-shrinkable material, is providedand each individual wrapper is positioned in a partially openconfiguration to receive and enclose a shoe on the wearers foot. Afterinsertion of the foot within the wrapper, a supply of heat such as acurrent of warm air, is directed over the wrapper to shrink the materialon the shoe so that the wrapper conforms to the shoe and fully enclosesthe same. 7

For use in operating rooms or other places where explosive atmospheresmay be encountered, each of the shoe wrappers may be provided with aconductive strip secured to the sole of the wrapper and adapted tocontact the leg of the wearer at its other end, thereby to preventdischarges of static electricity between the foot of the wearer and thefloor.

The above, and other objects, features and advantages of this inventionwill be apparent in the following detailed description of illustrativeembodiments of the invention which are to be read in connection with theaccompanying drawings wherein:

FIG. 1 is a perspective view of a device, according to an embodiment ofthe present invention, adapted to heat-shrink a plastic overshoe or bootonto the shoe of a wearer;

FIG. 2 is a perspective view of a plastic overshoe or boot formed inaccordance with the present invention,

FIG. 3 is a perspective view of the boot shown in FIG. 2, sealed on thefoot of a wearer after the heatshrink operation;

FIG. 4 is a side view, in section, of the device of FIG. 1, taken alongline 4-4 of FIG. 1;

FIG. 5 is a partial front view, in section, taken along line 5-5 of FIG.4 showing the left half of the device of FIG. 1;

FIG. 6 is a plan view of a portion of the device taken along line 6-6 ofFIG. 5, with the leg shields removed;

FIG. 7 is a perspective view of another embodiment of the presentinvention;

FIG. 8 is a perspective view of an overshoe formed for use in theembodiment of the invention shown in FIG. 7;

FIG. 9 is a side view, in section, taken along line 9'-9 of FIG. 7

FIG. 10 is a plan view of a portion of the embodiment of the inventionshown in FIG. 7, taken along line 10- 10 of FIG. 9; and

FIG. 11 is a side view, in section, taken along line 11-11 ofFIG. 9.

Referring to the drawings in detail, FIG. 1 shows device 10, of a typeadapted to carry out the method of the present invention, generallycomprising housing 12 having a storage section 14 and plurality 16 ofheatshrink stations where shoe wrappers 18 are presented beneath legshields 20 for heat-shrinking about shoe on the feet of a wearer.

The wrappers placed on the foot of a wearer in this embodiment of theinvention are shown in FIG. 2 and are formed of a sheet of material, e.g., a film of a plastic such as polyethylene or a vinyl copolymer, whichis adapted to be heat-shrunk at relatively low temperatures. The wrapperis pre-formed as an oversized boot or overshoe having upper accessopening 22 and plurality 24 of rear edges which, as more fully describedhereinafter, are held in an open configuration at the heat'shrinkstation to permit insertion of a shoe on the foot of a wearer prior tothe heat-shrink operation. Wrapper 18 is shaped generally with roundedfront end or toe portion 26 to conform generally to the shape of a shoe,conveniently by heat-sealing the edges thereof, so that on. shrinkingthe wrapper will more readily conform to the general configuration of ashoe.

Strip 28 of conductive plastic material, such as a polyethyleneimpregnated with carbon black or metallic particles, is heat-sealed tosole 30 of the wrapper at end 32 thereof, and is looped about theexterior of the wrapper with second end 34 positioned within accessopening 22. After application of the overshoe, end 34 of strip 28 isinserted in shoe 36 to touch the ankle of the wearer and provide aground connection between the body and the floor, thus to preventdischarges of static electricity therebetween. It is contemplated thatstrip 28 be tucked into the arch section of the foot outside the sock sothat strip 28 may not touch the ankle but will provide an electricalconnection to the body. Alternatively, it is contemplated that wrapper18 itself may be completely formed of a conductive plastic material, inlieu of the use of strip 28.

After the heat-shrinking operation, as performed by the device anddescribed hereinafter, wrapper 18 conforms to shoe 36 on the foot of awearer, as seen in FIG. 3, to provide a pleasant appearing, comfortableand compact shoe covering which is sealed tightly to the shoe to preventescape of bacteria and other contaminants from the shoe to the ambientatmosphere, e.g., to a hospital operating room or a clean roomenvironment in which the wearer is working.

While the material used to form the shoe coverings in the preferredembodiments of this invention is impervious to air so as to preventescape of bacteria, etc., from the shoes, it is contemplated that theshoe covering may also be used in environments and in applicationswherein such a high degree of sterility is not required. For example,overshoes of the character described could be used by window dressers orcould also be used as foul weather overshoes. In these situations thewrapper material could be made air permeable by extremely smallperforations in the material to permit ventilation of the foot and shoe.These perforations would however be positioned or dimensioned so as toprevent water from penetrating the wrapper and entering the shoe.

If a material which shrinks anisotropically is employed as theheat-shrinkable film in forming boot 18, the material is aligned in thelongitudinal direction of the boot, so that the boot will shrink duringthe heatshrink operation more in the direction of the length of the footthan in the direction of its width. By this construction the material isnot tightened to a substantial extent adjacent edge 38 of the heel onshoe 36 so as to fracture or tear the material during walking. It iscontemplated also that the material may be provided with a reinforcingstrip of material at those portions on sole 30 thereof adjacent the heelto strengthen the material and avoid tearing during use.

To facilitate removal of the overshoe, tear strip or string 40 isembedded in the material forming wrapper 18 and is provided with looseend 42. Upon completion of use of the heat shrunk overshoe, end 42 ofstrip 40is grasped by the wearer, and pulled downwardly to tear thematerial. The overshoe is thereafter readily peeled from the shoe. It isalso contemplated, that where a conductive strip 28 is utilized, thisstrip may be heat sealed along a major portion thereof to the surface ofwrapper 18 so that end 34 thereof may be grasped, upon completion of useof the overshoe, to tear the material and permit its removal.

Wrappers 18 are formed as individual members and are wound on roll 44rotatably mounted in housing section 14. The wrappers are interconnectedby pairs of strings or plastic strips 46, 46a, secured to the wrappersby a heat-sensitive adhesive (e.g., glue or wax) to form an integralroll of boots. As seen in FIGS. 5 and 6, the pair of strips 46 aresecured to upper surface or sides 48 of wrapper 18, and pair of strips46a are secured to sole 30 of the wrapper. While in the preferredembodiment, wrappers 18 are individually formed, and separately securedto strips 46, 46a, it is contemplated that the wrappers also .can beprovided as an integral roll wherein the front and rear edges ofadjacent wrappers are connected by a perforated strip which is readilytorn on completion of the heat shrink operation by a slight footmovement.

The ends of strips 46 are respectively guided over rollers 52 mounted inleg shield 20 as shown in FIGS. 1 and 5. From rollers 52 strips 46extend through elongated aperture 54in support surface or platform 56and are secured to roll 58. Strips 46a extend along the surface ofplatform 56 through apertures 60 therein and are respectively secured totake-up pulleys 62. The latter are fixed to common shaft 64 adapted tobe simultaneously rotated with roll 58 by motor 66 mounted belowplatform 56 in housing 12. Motor 66 has drive shaft 67 extendingtherefrom on which drive pulley 68 is secured. Pulley 68 is connected bybelt 70 to pulley 72 mounted at one end of roll 58. Second pulley 74mounted on roll 58 drives pulley 76 on shaft 64 through belt 78, so thatwhile motor 66 is operating roll 58 and pulleys 62 are simultaneouslyrotated to draw wrappers 18 from roll 44 through aperture 57 in platform56 to heat shrink station 16.

Initially, overshoe heat shrink device 10 is prepared for operation bysecuring strips 46 and 46a to roll 58 and pulleys 62, as describedabove, with the first wrapper 18 on roll 44 in position at heat shrinkstation 16. As seen in FIGS. 1 and 4, wrapper 18 is held at station 16by pulleys 52 and 62 with access opening 22 and edges 24 in an openconfiguration permitting insertion of the wearers foot and shoe withinthe wrapper prior to the heat shrink operation.

In order to close the opened rear end of boot 18 after the wearer hasinserted his foot therein, a pair of jaws 80 are provided which areadapted to heat-seal sides 48 of wrapper 18 together adjacent the heelof shoe 36. Jaws 80 are formed as individual bars pivotally mounted bypins 82 on a transport plate 84 slidably mounted in recess 86 ofplatform 56. Recess 86 is formed by pair 88 of longitudinally extendingparallel stepped ledges having first stepped portions 90 which receivethe longitudinal edges of plate 84 and define aperture 92 therebetween.Jaws 80 extend along the upper surface of plate 84 and into secondstepped portions 94 of'ledges88 whereby bars 80 and plate 84 are locatedbelow the upper surface of platform 56 so that no obstruction is formedon the platform.

In order to provide a more pleasing appearance of the wrapper'after heatshrinking, it is desirable to heatseal sides 48together adjacent theheel of shoe 36 prior to the heat shrinking operation since wrappers 18are supplied in a uniform size being somewhat larger than a standardsize 13 shoe. Thus, plate 84 is mounted for sliding movementlongitudinallyon ledges 90 to provide an adjustment for the position ofheat-sealing jaws 80 thereby to closely secure wrappers 18 to varioussized shoes so that the overshoe, when shrunk, conforms tightly to theshoe itself. To move plate 84 and, thus, bars 80 to a position adjacentthe heel of shoe 36, rack 96 is provided on lower surface 98 of plate 84and engaged by spur gear 100. The latter is driven by motor 102 mountedon lower surface 104 of platform 56.

When the wearer inserts his foot within wrapper 18, he engages pressureswitch 106 mounted on platform 56 adjacent the ball of his foot, whichswitch activates motor 102 to drive gear 100 and thereby move rack 96and plate 84 towards the heel of his foot.

Contact or microswitch 108 is provided immediately in front of bars 80on the upper surface 110 of plate 84 to engage the heel of the shoe 36as plate 84 is moved beneath the shoe. Accordingly, when plate 84 ismoved towards shoe 36, i.e., towards the left in FIG. 4, a sufficientdistance to engage switch 108 with the heel of the foot, switch 108deactivates motor 102 to stop movement of plate 84 and simultaneouslyactivates motor 112. Motor 112 pivots bars 80 about pins 82 to move thebars to a vertical clamping position as seen in FIG. 5. It is noted thatwhile only one of the heat shrinking stations 16 is illustrated in FIGS.5 and 6, the other station is similarly constructed and operates in thesame manner as the described station.

Referring again to FIG. 5, it is seen that inner ends 1 14 of bars 80,adjacent pivots 82 are formed with interengaging quadrant gears 116. Oneof these gears is provided with an integral crank arm 118 which ispivotally connected, by link 119 to crank 120 fixed to drive shaft 121of motor 112. As motor 112 is operated, crank arm 120, and thus crankarm 118, is moved downwardly, thereby to pivot the bars 80 to thevertical position shown in phantom. As bars 80 move to the verticalposition, they engage sides 48 of wrapper 18 and moves the sides towardseach other and ultimately into contact with each other when the bars arein their fully extended vertical position.

A safety control device 101 is provided on plate 84 to prevent bars80'from being raised in the event that the bars are blocked as forexample by the heel of the foot. Control device 101 includes aphotoelectric cell pickup 103 mounted adjacent one edge 105 of plate 84and a light source 107 mounted adjacent opposite edge 109 which lightsource directs a beam of light towards pickup 103. Pickup 103 isconnected to a control circuit (not shown) which is operative to preventactivation of motor 112 should the light from source 107 be blocked.That is, if the heel of the foot is over bars 80, thereby obstructingpassage of light from source 103 to pickup 107, the bars will not bepivoted by motor 1 12. In this manner, damage to the bars and gears 116is avoided, as is any possibility of injury to the foot.

Each bar 80 has mounted thereon resistance wire 122 which is connectedto impulse heating unit 124 for heating wires 122. After bars 80 aremoved to their vertical position, unit 124 is automatically andsequentially operated to heat wires 122 and seal sides 48 together.After the heat sealing operation is completed, which operation generallytakes less than S'seconds, motor 112 issequentially operated in reverseto permit bars 80 to return to their horizontal position. Thereafter,heat, such as a draft of warm air is supplied to heat shrink stations 16to shrink the plastic wrappers about'the shoes.

Bars 80 are each provided with a second resistance wire 126 connected toan independent impulse heating unit (not shown) for simultaneous heatingwith wires 122. Wires 126 are located on bars 80 rearwardly of wires 126and may have either sharpened edges or be positioned so that they lie inoverlapped relation when bars 80 are raised. In this manner, wires 126act as a cutter during the heat sealing operation to cut any excessmaterial rearwardly of the heat seal. This excess material is thusseparated from the main body of the wrapper and is discharged from thedevice in a manner more fully described hereinafter.

Shield 20, of housing 12, defines an air plenum chamber 128 adjacenteach of the wrappers 18 at heat shrink stations 16. Warm air is suppliedto the plenum chambers through apertures 130 formed in platform 56adjacent recess 86. Air is provided from an electrically driven blower132 which flows air over electrically powered heating elements 134. Theair, thus warmed, is thence discharged through duct 136 to plenumchambers 128 formed above platform 56, as shown in FIG. 4. The air thussupplied is discharged through apertures 130 into plenum chambers 128and flows about wrappers 18. The heat supplied by the elements 134 issufficient to warm the air to a high enough temperature to permitshrinking of the copolymer material of which the wrapper is formed.Shield 20, limits discharge of warm air upwardly from the plenumchambers to protect the trousers and the leg from the warm air. However,it is noted that the temperature of this air is sufficiently low so thatsealing of the wrapper on the foot of the wearer is performed withcomplete safety I and the entire operation is performed at relativelycomfortable temperatures for the short period of time which theshrinking process takes. Blower 132 and heating elements 134 arecontrolled by a conventional timing circuit and after these elementshave been in operation for a period of time adequate to shrink thewrapper to the configuration shown in FIG. 3, they are automaticallyshut off and the foot may be removed from the device. A temperaturesensitive switch 137 is provided in the circuit controlling blower 132and heating elements 134, and this switch is located on platform 56,adjacent wrappers 18. Switch 137 is adapted to shut off blower 132 andheating elements 134 in the event that there is a malfunction in thedevice which causes them to continue in operation beyond thepredetermined period. Thus, should the temperature within plenumchambers 128 rise above a predetermined level, the hot air will beimmediately shut off. Further, in the preferred embodiment, heatingelements 134 and blower 132 shut off sequentially, with elements 134shutting off first, so that a flow of relatively cool air is supplied toplenum chambers 128 to carry heat away from the heated wrappers and setthe plastic material. Alternatively, a separate and independent blowermay be provided for this purpose.

During the heat shrinking operation, the remaining wrappers on roll 44are protected from the warm air by housing section 14. The volume of airentering this section through supply slot 57 in platform 56 isinadequate to damage these wrappers. Moreover, while the heat shrinkingoperation has been described using a supply of warm air, it iscontemplated that other known heat shrinking methods may be utilized. Inparticular, it is foreseen that sources of infrared radiation may beprovided to shrink wrappers 18.

As mentioned above, strips 46 and 46a are secured to wrappers 18 byheat-sensitive adhesive. Thus these strips are released from thewrappers during the heatshrinking operation, since the adhesive releasesor separates under the influence of the warm air supplied from blower132 and heater 134. The strips are formed of non-heat-shrinkablematerial and are in no way damaged by the heat-shrinking process.However, strips 46 are secured to wrappers 18 adjacent rear edges 24, asfor example at points 140 which are sufficiently remote from shoe 36 andapertures 130 so that that connection of the wrapper with the strips atthis point is not released. Thus, on completion of the heat shrinkingoperation, when the wearer removes his foot from the device, strips 46remain secured to the excess material removed from the boot by heatsealing bars 80 and their cutting edges 126.

Release of pressure on switch 106, by removal of the wearers foot,activates motor 66, after a suitable time delay, to rotate roll 58 andpulley 62. In this manner strips 46a are wound on pulleys 62 and strips46, along with the excess or waste portion of the prior boot are drawnthrough aperture 54 in platform 56 onto roll 58. Motor 66 is controlledby a conventional timing circuit and continues in operation for apredetermined period of time adequate to properly position the nextwrapper 18 on roll 44 at heat shrink station 16. Thereafter the cycle isrestarted by subsequent activation of switch 106. It is noted that thespecific electronic circuitry utilized in overshoe heat shrink device 10to control the various components thereof forms no part of the presentinvention, and is not described in detail. The sequential steps of thepresent invention may be controlled in numerous manners, as will beevident to those skilled in the art.

After the use of the overshoe is completed, wrapper 18 is convenientlyremoved from the foot of the wearer by tear strip 40. Free end 42 ofstring 40 is grasped and pulled downwardly to tear the relatively thinplastic material and free wrapper 18 from shoe 36. It is noted thatwhile the material is sufficiently thin to be torn by narrow string 40,the material is also sufficiently strong and durable to withstand normalusage and will not tear of its own accord. As mentioned above, it iscontemplated that conductive strip 28 may be heat-sealed along a thinline to the sides 48 of wrapper 18 so that it also may be used as a tearstrip.

Referring now to FIG. 7, there is illustrated in embodiment of thepresent invention which is adapted to heat shrink preformed overshoes ona shoe on the foot of a wearer. As seen therein, overshoe heat shrinkdevice includes housing 152 having storage section 154 and pair 156 ofheat shrink stations. Leg shields 158 are provided at stations 156, andcorrespond substantially to shields 20 of the previously describedembodiment. In this embodiment, fully formed oversized wrappers 160 areprovided, as seen in FIG. 8. Wrappers 160 have enlarged access opening162 at the upper surface thereof through which the foot of the wearer isinserted.

Initially, wrappers 160 are in position at heat shrink stations 156 andthe wrappers are opened to a limited extent, from their prior foldedconfiguration, because of their own natural resiliency. When the wearerdesires to place the wrappers upon his feet, he steps onto the forwardportion of platform 164, including pads 166, and thereby activatespressure switches 168 mounted below the pads. Switches 168 control ablower or source of suction 170 which is connected by a pair of ducts172 to plenum chambers 174. Chambers 174 are mounted on the lowersurface 176 of platform 164 at opposite sides of heat shrink stations156 and communicate with plenum chamber 177 formed by shield 158 aboutstation 156 through apertures 180 in platform 164. Suction source 170creates a low pressure atmosphere in plenum chambers 177 by drawing airfrom the chamber through chamber 174 and ducts 172. Simultaneously,source 170 supplies this air to jets 182 having nozzles 184 directedinto access opening 162 to partially inflate the overshoe. Thus, thecombination of the low pressure within plenum chamber 177 and the forceof the jets of air discharged from source 170 to jet nozzles 184 intoaccess opening 162 of wrappers 160 opens the wrappers to facilitateinsertion of the shoe therein.

To further facilitate insertion of shoe 36 within wrappers 160 and toenlarge the access opening presented to the shoe for insertion,hold-down mechanism 186 is provided for the heel of the wrapper.Hold-down mechanism 186 includes a pair of plenum chambers or suctioncups 188, each of which is pivotally mounted by arms 189 on platform 164adjacent opposite sides of heel 190 of wrapper 160. Arms 189 eachinclude a rigid lever 192 which levers are pivotally connectedrespectively, by links 194 to solenoids 196 for operative control of theposition of cups 188. Suction cups 188 include a perforated face 198which encloses a chamber 200 connected by flexible conduit 191 to sourceof suction 170. Activation of pressure switch 168 simultaneouslyactivates source of suction 170 and solenoids 196 so that arm 189 isfirst pivoted downwardly to engage face 198 of cup 188 with heel 190 ofwrapper 160. Since plenem chamber 200 is connected to source of suction170, a low pressure area is produced in chamber 200 which causes heel190 to be secured to face 198. After cups 188 reach their lowermostposition solenoid 196 is operated in reverse to raise the cups and theheel 190 in conjunction therewith to enlarge the access opening in thewrapper. In FIG. 7, suction cups 188 in each heat-shrink station 156 arerespectively shown in their raised and lowered positions for clarity inunderstanding this operation.

After the physicians feet are inserted in wrappers 160, they aresupported at heat-shrink stations 156 by wrapper transport plates 202whose principal function is described more fully hereinafter. Plates 202are mounted for sliding movement in recesses 204 on longitudinallyextending ledges 206 adjacent the sides thereof. The pressure of thewearers weight on plate 202 activates pressure-sensitive switch 208positioned on ledge 206 which deactivates suction source 170.Simultaneously, blower 210 and heating elements 212 are activated, whichelements supply warm air to plenum chamber 174. Blower 210 blows airover heating elements 212 and supplies the warmed air through duct 214to plenum chamber 174 wherein the warm air is discharged throughapertures 180 to plenum chamber 177. The air is thereby flowed over thesurface of heat-shrink wrapper 160 to shrink the material of which thewrapper is made and conform the wrapper to the shoe. As in the priorembodiment, blower 210 and heating element 212 are controlled by aconventional timing circuit so that after a period of time, adequate toshrink the material forming wrappers 160, the blower and heatingelements are sequentially shut off so that a flow of relatively cool airis supplied to set the molten plastic. When the blower shuts off,thermal shut off switch or control 137 may also be provided-in thecircuit for blower 210 and heater 212 to shut off the system in theevent of malfunction which causes the temperature in plenum chambers 177to rise above a predetermined level. As in the prior embodiment, theparticular electronic circuitry utilized in conjunction with the presentinvention to perform the various operations thereof are within the skillof the ordinary artisan and illustration of specific circuits isomitted.

When the wearers foot is removed from heat-shrink station 156, pressureon switch 208 is released and after a suitable time delay, transportplate 202 is operated to move a wrapper 160 from storage station 213within housing section 154. Wrappers 160 are supplied to storage station213 in stacks 211 seated on movable platforms 215. Platforms 215 areslidably mounted on ledge .206 associated respectively with each of theheat-shrink stations 156.

Each platform 215 is mounted on a pair of rods 217 secured to the rearwall 216 of housing 152. Each of the rods 217 is provided with acompression spring 219 surrounding the rod, which springs urge platform215 into position beneath the stack of wrappers.

Release of switch 208 activates air cylinder 218 which is adapted toreciprocate transport plate 202 from heat-shrink station 156, alongledges 206, to storage station 213. As plate 202 is moved towards plate215, plate 202 engages plate 215 and moves the latter from beneath stack211 and towards wall 216 while stack 211 is held stationary by baffle230. At the end of the stroke of piston 218, the rearward end 221 ofplate 215 is engaged with a switch 220. Switch 220 activates a vacuumsource 222 which decreases the pressure beneath plate 202 to secure anindividual wrapper to the surface thereof. Plate 202 has plenum chamber224 formed therebeneath and connected by flexible conduit 226 to sourceof suction 222. Chamber 224 is thus moved with plate 202 from heatshrink station 156 to storage station 213. Cylinder 218 is then operatedin reverse to withdraw plate 202 and an individual wrapper 160, which issecured thereto by the suction force produced by member 222 from station213 back to the heat-shrink station 156. At the same time, plate 215 isurged back to position beneath the stack 211 by springs 219 to maintainthe remainder of the overshoes within the stack and in position forsubsequent operations.

In this embodiment of the present invention it is seen that there is nowaste, as a fully formed heat-shrink boot is provided and there is noexcess cut off portions of the boot by heat sealing jaws as in the priorembodiment. The material of the boots in this embodiment of theinvention is similarly aligned in the manner earlier described so thatthe material shrinks more in the direction of length than in width andthereby provides a relief area adjacent the forward edge of the heel sothat the material is not damaged or torn by the heel during use.

For hospital use, each of the above-described embodiments of the presentinvention can be incorporated into a console unit (not shown) at whichthe physician may perform other procedures while having the sanitaryovershoes automatically applied to his feet. For ex-' ample, the consolemay contain a supply of surgical hats, surgical masks, and gowns whichthe physician may put on during the time in which the booting operationis taking place. It is also contemplated that such a console may containa supply of heat shrinkable overshoes which may be manually applied tothe physicians foot. The above-described apparatus may then be used toheat shrink the wrappers, or alternatively, the console may include awarm air blower which can be held manually and utilized to shrink thewrappers. I

It is thus seen that a sample and relatively convenient sanitary shoewrapping is provided which is readily, placed on the foot of the wearerand which is neatand clean in appearance and comfortable in use.Further, the overshoes of the present invention are both for right andleft feet, so that a singleoverwrapper will fit either foot and thussubstantially reduce the cost of manufacturing the wrappers. Moreover,the wrappers are relatively inexpensive, thus disposable, and. they arerapidly and conveniently applied to the shoes of the wearer by themethods of the present invention.

Although illustrative embodiments of the present invention have beendescribed herein with reference to the accompanying drawings, it is tobe understood that the invention is not limited to those preciseembodiments, and that various changes and modifications 'may be effectedtherein by one skilled in the art without departing from the scope orspirit of this invention.

What is claimed is:

l. The method of covering a shoe on the foot of a wearer with aprotective wrapper, comprising the steps of positioning said wrapper forinsertion of said shoe and foot therein, inserting said shoe and foot inthe wrapper, and, after insertion of said shoe, heat shrinking saidwrapper about said shoe, whereby said wrapper conforms to said shoe.

2. The method as in claim 1 wherein said wrapper is preformed, saidmethod including the step of holding said wrapper in an openconfiguration for insertion of said shoe and foot therein.

3. The method as in claim 2 wherein said holding step includes the stepof blowing air into said wrapper.

spaced relation to permit insertion of said shoe in said wrapper.

6. The method as in claim including the step of sealing said openwrapper sides after insertion of said shoe.

7. The method as in claim 6 wherein said sealing step comprises the stepof heat sealing said sides.

8. The method as in claim 1 wherein said step of heat shrinkingcomprises the step of directing infrared radiation at said shoe and saidwrapper.

9. The method as in claim 5 including the steps of sensing the size ofsaid shoe after insertion in said wrapper and sealing said wrapper sidesadjacent said shoe to enclose said shoe prior to said heat-shrinkingstep.

10. The method of claim 9 wherein said sealing step comprises the stepof moving a pair of heat sealing jaws toward each other with said opensides therebetween.

l l. The method of claim 10 wherein said sensing step includes the stepof moving said jaws to a position adjacent the heel of said shoe priorto said heat sealing step.

12. The method of claim 10 including the step of cutting off excessportions of said sides.

13. The method of claim 1 including the step of forming said wrapperwith an electrically conductive strip to provide a ground contactbetween the body of the wearer and the floor.

14. The method of claim 13 including the step of heat sealing a portionof said strip to said wrapper along a relatively narrow band, wherebysaid strip comprises a tear strip for opening said wrapper after use.

15. The method of claim 13 including the step of forming a tear strip insaid wrapper for opening said wrapper after use.

16. The method of claim 1 including the step of forming said wrapperfrom a conductive heat shrinkable material.

17. The method of covering a shoe on the foot of a wearer with aprotective wrapper, comprising the steps of holding an oversizedprotective shoe shaped wrapper formed of heat shrinkable material in anopened configuration for insertion of said shoe and foot therein,inserting said shoe and foot in the open wrapper, and heat shrinkingsaid wrapper about said shoe to conform the wrapper to the shoe.

18. The method as in claim 17 wherein said step of 12 heat shrinkingcomprises the step of supplying a flow of warm air over said wrapper andsaid shoe to heat shrink said wrapper.

19. The method of claim 17 including the step of forming said wrapperwith an electrically conductive strip to provide a ground contactbetween the body of the wearer and the floor.

20. The method of claim 19 including the step of forming a tear strip insaid wrapper for opening said wr r after use.

protective shoe covering comprising an oversized generally shoe-shapedwrapper having an access opening therein for insertion of a shoe whilesaid shoe is on the foot of a wearer, said wrapper being formed of aheat-shrinkable material to be tightly drawn onto the shoe by anapplication of heat to the wrapper after the wrapper is placed on theshoe, thereby to define a sole and top portion surrounding this sole,heel and upper of said shoe.

22. A protective shoe covering as in claim 21 wherein said wrapper is afully formed oversized overshoe and said access opening is in the topthereof..

23. A protective shoe covering as in claim 21 wherein said wrapper isformed with a toe portion, a sole portion, and spaced side portionsrearwardly of said toe portion, said side portions defining said accessopening in the heel and upper portion of said wrapper.

24. A protective shoe covering as in claim 21 wherein said material iselectrically conductive.

25. A protective shoe covering as in claim 21 including an electricallyconductive strip of material secured at one end to the sole of saidwrapper, the other end of said strip being positioned adjacent saidaccess opening and adapted to be placed in contact with the skin of thewearer for conducting electricity from the wearers body to the floor.

26. A protective shoe covering as in claim 25 wherein said strip is heatsealed to said wrapper.

27. A protective shoe covering as in claim 25 wherein said strip is heatsealed to said wrapper along a relatively narrow portion thereof,whereby said strip forms a tear strip for ripping said wrapper uponcompletion of use to facilitate removal thereof from said shoe.

28. A protective shoe covering as in claim 21 including a tear stripsecured to said wrapper for tearing said wrapper upon completion of useto facilitate removal thereof from said shoes.

29. A protective shoe covering as in claim 21 wherein said material isalinged to shrink to a substantially greater extent in length than inwidth.

30. A protective shoe covering as in claim 21 wherein said material isair permeable.

1. The method of covering a shoe on the foot of a wearer with aprotective wrapper, comprising the steps of positioning said wrapper forinsertion of said shoe and foot therein, inserting said shoe and foot inthe wrapper, and, after insertion of said shoe, heat shrinking saidwrapper about said shoe, whereby said wrapper conforms to said shoe. 2.The method as in claim 1 wherein said wrapper is preformed, said methodincluding the step of holding said wrapper in an open configuration forinsertion of said shoe and foot therein.
 3. The method as in claim 2wherein said holding step includes the step of blowing air into saidwrapper.
 4. The method as in claim 1 wherein said step of heat shrinkingcomprises the step of supplying a flow of warm air over said wrapper andsaid shoe to shrink said wrapper.
 5. The method as in claim 1 whereinsaid positioning step includes the step of holding said wrapper in apartially open configuration with at least two of its sides in spacedrelation to permit insertion of said shoe in said wrapper.
 6. The methodas in claim 5 including the step of sealing said open wrapper sidesafter insertion of said shoe.
 7. The method as in claim 6 wherein saidsealing step comprises the step of heat sealing said sides.
 8. Themethod as in claim 1 wherein said step of heat shrinking comprises thestep of directing infrared radiation at said shoe and said wrapper. 9.The method as in claim 5 including the steps of sensing the size of saidshoe after insertion in said wrapper and sealing said wrapper sidesadjacent said shoe to enclose said shoe prior to said heat shrinkingstep.
 10. The method of claim 9 wherein said sealing step comprises thestep of moving a pair of heat sealing jaws toward each other wIth saidopen sides therebetween.
 11. The method of claim 10 wherein said sensingstep includes the step of moving said jaws to a position adjacent theheel of said shoe prior to said heat sealing step.
 12. The method ofclaim 10 including the step of cutting off excess portions of saidsides.
 13. The method of claim 1 including the step of forming saidwrapper with an electrically conductive strip to provide a groundcontact between the body of the wearer and the floor.
 14. The method ofclaim 13 including the step of heat sealing a portion of said strip tosaid wrapper along a relatively narrow band, whereby said stripcomprises a tear strip for opening said wrapper after use.
 15. Themethod of claim 13 including the step of forming a tear strip in saidwrapper for opening said wrapper after use.
 16. The method of claim 1including the step of forming said wrapper from a conductive heatshrinkable material.
 17. The method of covering a shoe on the foot of awearer with a protective wrapper, comprising the steps of holding anoversized protective shoe shaped wrapper formed of heat shrinkablematerial in an opened configuration for insertion of said shoe and foottherein, inserting said shoe and foot in the open wrapper, and heatshrinking said wrapper about said shoe to conform the wrapper to theshoe.
 18. The method as in claim 17 wherein said step of heat shrinkingcomprises the step of supplying a flow of warm air over said wrapper andsaid shoe to heat shrink said wrapper.
 19. The method of claim 17including the step of forming said wrapper with an electricallyconductive strip to provide a ground contact between the body of thewearer and the floor.
 20. The method of claim 19 including the step offorming a tear strip in said wrapper for opening said wrapper after use.21. A protective shoe covering comprising an oversized generallyshoe-shaped wrapper having an access opening therein for insertion of ashoe while said shoe is on the foot of a wearer, said wrapper beingformed of a heat-shrinkable material to be tightly drawn onto the shoeby an application of heat to the wrapper after the wrapper is placed onthe shoe, thereby to define a sole and top portion surrounding thissole, heel and upper of said shoe.
 22. A protective shoe covering as inclaim 21 wherein said wrapper is a fully formed oversized overshoe andsaid access opening is in the top thereof.
 23. A protective shoecovering as in claim 21 wherein said wrapper is formed with a toeportion, a sole portion, and spaced side portions rearwardly of said toeportion, said side portions defining said access opening in the heel andupper portion of said wrapper.
 24. A protective shoe covering as inclaim 21 wherein said material is electrically conductive.
 25. Aprotective shoe covering as in claim 21 including an electricallyconductive strip of material secured at one end to the sole of saidwrapper, the other end of said strip being positioned adjacent saidaccess opening and adapted to be placed in contact with the skin of thewearer for conducting electricity from the wearer''s body to the floor.26. A protective shoe covering as in claim 25 wherein said strip is heatsealed to said wrapper.
 27. A protective shoe covering as in claim 25wherein said strip is heat sealed to said wrapper along a relativelynarrow portion thereof, whereby said strip forms a tear strip forripping said wrapper upon completion of use to facilitate removalthereof from said shoe.
 28. A protective shoe covering as in claim 21including a tear strip secured to said wrapper for tearing said wrapperupon completion of use to facilitate removal thereof from said shoes.29. A protective shoe covering as in claim 21 wherein said material isalinged to shrink to a substantially greater extent in length than inwidth.
 30. A protective shoe covering as in claim 21 wherein saidmaterial is air permeable.